Bump grpcio in /examples/reservations-bot-demo/cloud_function

Bumps [grpcio](https://github.com/grpc/grpc) from 1.53.0 to 1.53.2.
- [Release notes](https://github.com/grpc/grpc/releases)
- [Changelog](https://github.com/grpc/grpc/blob/master/doc/grpc_release_schedule.md)
- [Commits](grpc/grpc@v1.53.0...v1.53.2)

---
updated-dependencies:
- dependency-name: grpcio
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

examples/reservations-bot-demo/cloud_function/requirements.txt

@@ -4,7 +4,7 @@ chardet==3.0.4
 cryptography==41.0.0
 enum-compat==0.0.3
 googleapis-common-protos==1.52.0
-grpcio==1.53.0
+grpcio==1.53.2
 idna==2.10
 protobuf==3.18.3
 pycparser==2.20